The 53rd International 500 Mile Sweepstakes was held at the Indianapolis Motor Speedway in Speedway, Indiana on Friday, May 30, 1969. Mario Andretti led 116 laps and won for car owner Andy Granatelli. Hard luck driver Lloyd Ruby was leading the race just after the midpoint, but during a pit stop, pulled away with the fueling hose still attached. He ripped a hole in the fuel tank, and was out of the race. The incident put Mario Andretti in the lead for rest of the way. Andretti's victory capped off an up-and-down month of May. He entered the month as a favorite, but he crashed his primary car during practice. Andretti suffered burns but was able to qualify in a back up car for the middle of the front row. Mario Andretti's 1969 Indy 500 win is the lone victory in the race for the storied Andretti racing family. As of 2016, no Andretti has won the Indianapolis 500 since.

Polesitter A. J. Foyt led the race in the early stages, looking to become the first four-time winner of the 500. Near the halfway point, however, a lengthy pit stop to repair a broken manifold put him many laps down. Despite a hard-charging run towards the end, he wound up managing only an eighth place finish, 19 laps down.

For 1969 not a single front-engined car managed to qualify for the race, and ultimately, one would never do so again. All 33 cars in the field were rear-engined, piston-powered, machines. After the historic failures of the controversial STP Granatelli Turbine machines in 1967 and 1968, USAC imposed additional restrictions that effectively rendered them uncompetitive. The annulus inlet was further reduced from 15.999 in² to 11.999 in², and the Granatelli team parked them forever.

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